Description of the liquid-vapor phase equilibrium line of pure substances within the bounds of scale theory based on the Clapeyron equation

On the basis of the Clapeyron equation and the scale theory, expressions are developed for the “apparent” heat of vaporization r * = r * (T), vapor ρ- = ρ- (T) and liquid ρ+ = ρ+ (T) branches of the saturation line of individual substances for the range of state parameters from the triple point (pt,Tt,ρt ) to the critical (pc,Tc,ρc ). The peculiarity of the proposed approach to the description of the saturation line is that all exponents of the components of the equations ρ- = ρ- (T) and ρ+ = ρ+ (T) are universal up to the universality of the critical indices α, β and Δ. In this case, the order parameter ds = (ρ+ − ρ-)/(2ρc) and the average diameter df = (ρ+ + ρ-)/(2ρc) − 1 of the saturation line satisfy the saturation line model [2β,1−α], which follows from the modern theory of critical phenomena. The method is tested on the example of describing the phase equilibrium line of refrigerant R1233zd(E) in the range from Tt = 195.15 K to Tc = 439.57 K. It is found that in the temperature range [Tt,Tc ], the developed system of the mutually consistent equations ps = ps (T), r * = r * (T), ρ- = ρ- (T) and ρ+ = ρ+ (T) allows describing the data on the saturated vapor pressure ps and densities ρ- and ρ+ on the saturation line within the experimental uncertainty of these data.

Calculation and Plot of Predominance Area Phase Diagram for Cu-S-O Ternary System

The typical chemical reactions of metal were analyzed in this paper, and the two-phase equilibrium line calculated model was obtained. By use of the physical properties database, the design of chemical reactions and the compounds were to be determined. Through the calculating the two-phase point and three-phase point ,the predominance area phase diagram algorithm based on the physical properties database was formed, which has clear physical meaning and accuracy calculation result, and also whose result was consistent with that of the literature.

Calculation of the Multiphase Equilibrium of the Reaction in Wet Flue Gas Desulfuration

A computational code, which can be used to calculate gas-liquid-solid 3-phase equilibrium line, has been developed based on the principle of free energy minimum. Then the equilibrium lines of dissolution of SO2 and CaCO3 in water are obtained using the code. The results satisfy the mass and charge conservation and match well with the data in the references. Finally, multiphase equilibrium lines of the reaction in WFGD are calculated in different conditions. The results show that temperature, concentration of SO2, CO2, have different effects on the solubility of SO2 under initial conditions given in the paper. Temperature and concentration of SO2 have great effects, and the concentration of CO2 has a small effect. The solubility of SO2 increases as the partial pressure of SO2 increases, temperature decreases or the concentration of CO2 decreases. These conclusions have a great guidance on designing the tower of wet flue gas desulphurization.